Non-invasive Ultrasound Based Temperature Measurements at Reciprocating Screw Plastication Units: Methodology and Applications
Sprache des Vortragstitels:
Englisch
Original Tagungtitel:
30th International Conference of the Polymer Processing Society
Sprache des Tagungstitel:
Englisch
Original Kurzfassung:
Previous attempts to accurately measure the real polymer melt temperature in the screw chamber as well as in
the screw channels have failed on account of the challenging metrological boundary conditions (high pressure, high
temperature, rotational and axial screw movement). We developed a novel ultrasound system - based on reflection
measurements - for the online determination of these important process parameters. Using available pressure-volume-
temperature (pvT) data from a polymer it is possible to estimate the density and adiabatic compressibility of the material
and therefore the pressure and temperature depending longitudinal ultrasound velocity. From the measured ultrasonic
reflection time from the screw root and barrel wall and the pressure it is possible to calculate the mean temperature in the
screw channel or in the chamber in front of the screw (in opposition to flush mounted infrared or thermocouple probes).
By means of the above described system we are able to measure axial profiles of the mean temperature in the screw
chamber. The data gathered by the measurement system can be used to develop control strategies for the plastication
process to reduce temperature gradients within the screw chamber or as input data for injection moulding simulation.
Sprache der Kurzfassung:
Englisch
Englischer Vortragstitel:
Non-invasive Ultrasound Based Temperature Measurements at Reciprocating Screw Plastication Units: Methodology and Applications
Forschungs-